Hydraulic fracturing increases the flow of desirable fluids such as oil and gas from a subterranean formation and involves placing a fracturing fluid into a subterranean formation or zone at a rate and pressure sufficient to impart a stress in the formation or zone with attendant production of a fracture in the formation or zone.
Beyond creating the fracture, the fracturing fluid also transports a proppant into the fracture. The proppant keeps the fracture open after release of the exerted pressure. Further, the proppant establishes conductive means in which the formation fluids flow to the borehole. Since the proppant provides a higher conductivity than the surrounding rock, the fracture has greater potential for production of hydrocarbons.
Commercial superabsorbents hydrate and swell to many folds of their original sizes, and have been proposed to be used in hydraulic fracturing applications to transport and place proppant in created fractures.
To minimize phase separation or settling of proppant before the fracture closes, the loading of the superabsorbents has to reach a certain level. In practice, it is always desirable to minimize the amount of absorbent materials to allow for easier and more complete degradation or “break” to leave less formation or proppant pack damage and to reduce cost. Accordingly, there is a need for methods that improve the hydration and/or swelling efficiency of superabsorbents. It would be a further advantage if such methods can improve the hydration and/or swelling efficiency of superabsorbents under challenging conditions, such as in water having certain degree of salinity.